Seat assembly providing airflow path to cool batteries

ABSTRACT

Various aspects of the present invention relate to a vehicle seat assembly supportable on a floor of a vehicle having a battery pack disposed behind the vehicle seat, operable to help cool the battery pack, a vehicle battery pack cooling system, and a method of cooling a vehicle battery pack. In at least one embodiment, the vehicle seat assembly comprises a seat bottom comprising a structural support portion made of a first material and a foam seat cushion supported on the structural support portion, with the first material being more resilient than the foam. The structural support portion is supportable on the vehicle floor and, when supported on the floor, communicates with the vehicle floor to form an air flow passage extending under the seat bottom to provide air flow to the battery pack.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.11/755,301 filed May 30, 2007, which is incorporated herein byreference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a seat assembly that provides an airflow path to cool batteries.

2. Background Art

Vehicle battery cooling systems are known. Examples of known vehiclebattery cooling systems include U.S. Pat. Nos. 6,902,020; 6,662,891,6,541,151; 6,220,383; and 5,937,664; and U.S. Patent ApplicationPublication No. 2005/0011692.

SUMMARY OF THE INVENTION

According to at least one aspect of the present invention, a vehicleseat assembly is provided. In at least one embodiment, the vehicle seatassembly is supportable on a floor of a vehicle having a power sourcedisposed behind the vehicle seat. The vehicle seat assembly comprises aseat bottom and a seat back extending adjacent the seat bottom. In atleast this embodiment, the seat bottom comprises a structural supportmember made of a structural foam material and a cellular foam seatmember supported on the structural support portion with the structuralfoam material being more resilient than the cellular foam seat member.The structural support member is supportable on the vehicle floor and,when supported on the floor, is configured to provide an air flowpassage extending under the seat bottom to provide air flow to the powersource.

According to at least another aspect of the present invention, a vehiclebattery pack cooling system is provided. In at least one embodiment, thevehicle battery pack system comprises a vehicle floor, a seat assemblysupported on the vehicle floor, and a battery pack, for providing atleast some of the power to the vehicle, supported behind the seatassembly. The vehicle seat assembly comprises a seat bottom and a seatback extending generally vertically from the seat bottom. In at leastthis embodiment, the seat bottom comprises a structural support portionmade of a first material and a foam seat cushion supported on thestructural support portion. The structural support portion is supportedon the vehicle floor and the structural support portion communicateswith the vehicle floor to form at least a portion of an air flow passageextending under the seat bottom. The structural support portion furtherhas a plurality of spaced-apart support members cooperating with thevehicle floor to help support the seat assembly of the vehicle floor.

According to yet at least another aspect of the present invention, amethod of cooling a vehicle battery pack located in a vehicle having avehicle floor is provided. In at least one embodiment, the methodcomprises supporting a seat assembly on the vehicle floor and supportinga battery pack for providing at least some of the power to the vehiclebehind the seat assembly. The vehicle seat assembly comprises a seatbottom and a seat back. In at least this embodiment, the seat bottomcomprises a structural support portion made of a first material and afoam seat cushion supported on the structural support portion, with thefirst material being at least as resilient as the foam. In at least thisembodiment, the structural support portion communicates with the vehiclefloor to help form an air flow passage extending under the seat bottom.In at least this embodiment, the method further comprises directing airflow through the air passage under the seat to provide cooling to thebattery pack.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic perspective view of a system in accordance with anembodiment of the present invention;

FIG. 2 is a schematic sectional side view of components illustrated inFIG. 1, taken through line 2-2;

FIG. 3 is an exploded view of components illustrated in FIGS. 1 and 2;and

FIG. 4 is a schematic perspective view depicting the underside of acomponent illustrated in FIG. 3.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

As required, detailed embodiments of the present invention are disclosedherein. However, it is to be understood that the disclosed embodimentsare merely exemplary of the invention that may be embodied in variousand alternative forms. The Figures are not necessarily to scale, somefeatures may be exaggerated or minimized to show details of particularcomponents. Therefore, specific structural and functional detailsdisclosed herein are not to be interpreted as limiting, but merely as arepresentative basis for the claims and/or as a representative basis forteaching one skilled in the art to variously employ the presentinvention.

Moreover, except where otherwise expressly indicated, all numericalquantities in this description and in the claims are to be understood asmodified by the word “about” in describing the broader scope of thisinvention. Practice within any numerical limits stated is generallypreferred. Also, unless expressly stated to the contrary, thedescription of a group or class of materials by suitably or preferredfor a given purpose in connection with the invention implies thatmixtures of any two or more members of the group or class may be equallysuitable or preferred.

Referring now to the Figures, where like numerals are used to designatelike structures throughout the drawings, a schematic vehicle seatassembly in accordance with at least one embodiment of the presentinvention is generally shown at 10 in FIG. 1. While the vehicle seatassembly 10 is illustrated in FIG. 1 to be a bench seat assembly, itshould be understood that the principles of the invention are applicableto other types of seat assemblies, such as bucket, captain and othertypes of seat assemblies. It should also be understood that theprinciples of this invention are applicable to all types of vehicle seatassemblies as well as non-vehicle seat assemblies.

Referring to FIG. 1, the vehicle seat assembly 10 is shown secured to avehicle floor pan or a vehicle floor 12. The vehicle seat assembly 10can be secured in any suitable manner. A battery pack, schematicallyillustrated as 14, or any other suitable power source, such as anelectric motor, is shown to be disposed behind the seat assembly 10. Inthe illustrated embodiment, the battery pack 14 is disposed upon a ledgeof the vehicle floor 12 behind the seat assembly 10. The power source 14can be any suitable battery pack or power source such as an electricmotor, for helping to power the vehicle. For instance, the battery pack14 could be a battery pack or electric motor for an electric vehicle, ahybrid vehicle, or other types of vehicles. As will be explained belowin further details, the seat assembly 10 along with the vehicle floor 12forms an air flow path 15 which helps direct air, schematicallyillustrated as 17, from the vehicle occupant compartment 13 to thebattery pack 14 to cool the battery pack. The air can be from thevehicle occupant compartment or it can be conditioned air from a unitspecifically directed into the flow path 15.

The vehicle seat assembly 10 includes a seat back, generally indicatedat 16, and a lower seat assembly, generally indicated at 18. In at leastthe illustrated embodiment, the lower seat assembly 18 has a cushioncomposite 20 covered by a trim material 22. The seat back 16 can be anysuitable type of seat back.

The vehicle seat assembly 10 may also include a seat frame, (not shown)having a plurality of mounting brackets (not shown) adapted tooperatively secure the seat frame within a vehicle. The seat frame maybe constructed from any material suitable for application within avehicle seat assembly 10, such as aluminum, steel or other metal alloy,composite material, or a suitable polymer. Further, the seat frame maybe manufactured using techniques commonly known in the art, and relativeto the type of material employed. By way of example, manufacturingtechniques may include stamping, welding, fastening or molding asuitable material to form the seat frame.

As will be explained further below, it should be understood that theframe could optionally be omitted as desired. The cushion composite 20is received on or around the frame and the trim material 22 is adaptedto engage the cushion composite 20 and/or the frame in a coveringrelationship.

In at least one embodiment, the cushion composite 20 includes astructural layer 30, disposed over a frame (not shown), and a cushionlayer 32 that is disposed over the structural layer 30.

In at least one embodiment, the structural layer 30 can be any suitablestructural foam material. In at least one embodiment, suitablestructural materials will have a rigidity and/or density that is higherthan conventional open-cell (cellular) polyurethane foam that istypically employed in seat cushions. In at least one embodiment,suitable structural foam materials have a density of at least 1.75pounds per cubic foot (pcf), and less than 7.0 pcf. In at least anotherembodiment, suitable structural foam materials will have a density of2.0 to 4.0 pcf, and in yet other embodiments of 2.5 to 3.5 pcf. Densityof the structural foam material can be measured in accordance with ASTMtest method No. D3575.

In at least one embodiment, suitable structural materials will have acompressive strength, at 50% strain, of 0.30 to 0.50 MPa, in at leastanother embodiment of 0.32 to 0.42 MPa, and in at least anotherembodiment of 0.35 to 0.39 MPa. Compressive strength can be measured byASTM test method No. D3575. In at least one embodiment, suitablestructural materials will have a tear strength of 1.8 to 3.2 gms/mm, inat least another embodiment of 2.2 to 3.0 gms/mm, and in at leastanother embodiment of 2.4 to 2.8 gms/mm, as measured in accordance withASTM test method No. D3575. In at least one embodiment, suitablestructural materials will have flexural modulus of 12.5 to 18 MPa, in atleast another embodiment of 13.25 to 17 MPa, and in at least anotherembodiment of 13.5 to 15.5 MPa, as measured in accordance with ASTM testmethod No. D3575.

In at least one embodiment, the structural layer 30 comprises a moldedexpanded polyolefin (EPO) layer. Suitable examples of expandedpolyolefin (EPO) include, but are not necessarily limited to, expandedpolyethylene (EPE), expanded polypropylene (EPP), expanded polybutylene(EPB), and copolymers of ethylene, propylene, butylene, 1,3-butadiene,and other olefin monomers, such as alpha-olefin monomers having from5-18 carbon atoms, and/or cycloalkylene monomers such as cyclohexane,cyclopentene, cyclohexadiene, norbornene, and aromatic substitutedolefins, such as styrene, alpha-methylstyrene, paramethylstyrene, andthe like.

In at least one particular preferred embodiment, the EPO is expandedpolypropylene (EPP) and its copolymers with ethylene, propylene andbutylene. Any suitable EPP may be used, however in at least oneembodiment, suitable EPP's include, but are not limited to, ARPRO® EPPavailable from JSP International and EPP available from SCA PackagingNorth America.

Expanded polyolefins can be prepared by a bead polymerization process inwhich relatively small uniform beads of polymer are produced, containinga gas which is later utilized to effect blowing during the moldingprocess. The most commonly used gas is air although other gasesincluding low boiling point liquids which produce gases at the moldingtemperatures may be used. Suitable gases include, but are not limited toair, nitrogen, carbon dioxide, pentene and the like.

While the structural layer 30 can have any suitable size andconfiguration, in at least one embodiment, the structural layer 30 hasan average thickness of 5 to 100 mm, in other embodiments of 20 to 70mm, and in yet other embodiments of 30 to 50 mm.

Although the structural layer 30 has been mainly referred to herein as astructural foam material, it should be understood that the structurallayer 30 could also be made of a suitable plastic or metal, however, ithas been found that structural foam provides certain benefits relatingto recyclability and weight reduction.

The cushion layer 32 can comprise any suitable cushion material, such asa suitable resilient polymer. In at least one embodiment, suitablecushion materials will have a density of 1.5 to 4.5 pcf, in anotherembodiment of 2.0 to 3.75 pcf, and in yet other embodiments of 2.7 to3.0 pcf. Density of the cushion material can be measured by ASTM testmethod No. D3575. In at least one embodiment, suitable cushion materialswill have a compressive strength, at 50% strain, of 0.017 to 0.030 MPa,in other embodiments of 0.018 to 0.024 MPa, and in yet other embodimentsof 0.020 to 0.023 MPa. In at least one embodiment, suitable cushionmaterials will have a hysteresis of 18 to 30 KPa, in another embodimentsof 20 to 28 KPa, and in yet other embodiments of 23-26 KPa. Hysteresisof the cushion material can be measured by ASTM test method No. D3575.

In at least certain embodiments, the cushion material comprisesconventional polyurethane foam, soy-based foam, silicone, thermoplasticolefins, thermoplastic urethanes, and/or natural oil-based expandedpolyurethanes and the like. In at least one embodiment, because of itsenvironmentally friendly nature, soy-based polyurethane is preferred.Soy-based polyurethane can be made with any suitable soy-based polyols,such as those available, but not necessarily limited to, from Bayer,Urethane Soy Systems, and Dow Chemical. Any suitable soy-basedpolyurethane may be used, however in at least one embodiment, suitablesoy-based polyurethanes include, but are not necessarily limited tothose available from Woodbridge Foam and Renosol. The cushion layer 32can be any suitable size and shape, however, in at least one embodiment,the cushion layer 32 has an average thickness of 20 to 100 mm, and in atleast another embodiment of 30 to 70 mm, and in still yet otherembodiments of 40 to 60 mm.

It should be understood that the structural layer 30 and the cushionlayer 32 can have any suitable configuration, shape and size. Forinstance, as shown in the figures, each layer 30 and 32 have a similarsize and construction with the cushion layer 32 being disposed over thestructural layer 30.

As can be envisioned, many different configurations of the layers 30 and32 can be encompassed by the present invention, even those which are notshown or described herein.

As discussed, the vehicle seat assembly 10 also includes trim material22 which is adapted to engage the cushion composite 20 in a coveringrelationship. The trim material 22 may include any material known in theart. By way of example, some of the known materials include cloth,leather or polymers of sufficient quality and thickness for use in seattrim applications. Polymer trim materials may include a flexible closecell polymer skin material such as polyvinyl, polyvinyl chloride (PVC),polyester, nylon, thermoplastic olefin (TPO) or thermoplastic urethane(TPU). Additional materials for use as trim material 22, may include afoam backing (not shown, but generally known in the art) which may bemanufactured from a variety of polymer foam materials. By way ofexample, the foam backing may be polyethylene, polypropylene,polyurethane, or a polystyrene foam. Optionally, a mesh or reinforcingmaterial (not shown, but generally known in the art) such as fiberglass,nylon, polyester or natural fibers may be applied to the foam backing orback of the trim material 22 for increase in strength without increasingrigidity. In at least one particularly preferred embodiment, the trimmaterial 22 comprises polyester or nylon trim material having polyesteror nylon trim fasteners (not shown) for securing the trim material 22 toone or more components (i.e., cushion 20 and/or frame) of the vehicleseat assembly 10.

In at least certain embodiments, the layers 30 and 32 of the cushioncomposite 20 are configured so that they can be easily assembled anddisassembled to facilitate assembly and end of line disassembly forrecycling. In at least one embodiment, the layers 30 and 32 are notsecured to each other by a mechanical fastening. In this embodiment, thelayers 30 and 32 are either placed over each other and/or withinrecesses of an adjustment layer and held together by the overlying trimmaterial 22. In other embodiments, the layers 30 and 32 can have one ormore mechanical fastening component to secure the layers 30 and 32 toeach other.

Referring to FIGS. 2 to 4, the structural layer 30 of the lower seatassembly 18 includes a top surface 40, a bottom surface 42, a frontsurface 44 and a rear surface 46. The front surface 44 has an opening 50that communicates with to the bottom surface 42. As shown in FIG. 1, agrill 52 or other suitable trim member is disposed over the opening 50to cover the opening while allowing air to enter into the opening. Thebottom surface 42 on the structural layer 30 includes a pair of sidewalls 56 that extend from the front surface 44 of the structural layer30 to the rear surface 46 of the structural layer 30.

The bottom surface 42 of the structural layer 30 also includes aplurality of depending structures such as bars 64 and rods 66 which helpto distribute the weight of the vehicle occupant evenly over the lowerseat assembly 18 of the vehicle seat assembly 10. Moreover, side walls56 also cooperate with the bars 64 and rods 66 to distribute the weightof the vehicle occupant.

Referring to FIG. 3, in at least the illustrated embodiment, the cushionlayer 32 has a depending rim portion 70 that fits over at least asubstantial portion of the front surface 44 of the structural layer 30.The cushion layer 32, at least in the illustrated embodiment, alsoincludes an opening 74 that is positioned over opening 50 of thestructural layer 30 and the trim cover 22 also includes an opening 78that is positioned over openings 50 and 74.

In at least certain embodiments, when the seat assembly 10 is secured tothe vehicle, the side walls 56 of the structural layer 30 extend fromthe bottom surface 42 of the structural layer 30 to the vehicle floor12. In at least certain embodiments, the vehicle floor 12 and the sidewalls 56 and the bottom surface 42 of the structural layer 30 cooperateto define an air flow path 15 that extends under the structural layer30, and thus the lower seat assembly 18, to provide a path 15 for cooledair 17 to extend underneath the seat assembly 10 back toward the batterypack 14. A fan, shown schematically at 31, can be provided for drawingair to the battery pack 14. While fan 31 is illustrated as being locatedbehind battery pack 14 in FIG. 2, it should be appreciated that batterypack 14 could be located behind fan 13 or that fan 13 could be omittedor replaced with another air moving device.

After the air flows into the opening 50 of the structural layer andthrough the air flow path 15 under the lower seat assembly 18, the airis then directed out of the back of the lower seat assembly and behindthe seat back 16 to the battery pack 14.

While embodiments to the invention has been illustrated and described,it is not intended that these embodiments illustrate and describe allpossible forms of the invention. Moreover, the words used in thespecification are words of description rather than limitation, and it isunderstood that various changes may be made without departing from thespirit and scope of the invention.

1. A vehicle seat assembly supportable on a floor of a vehicle having apower source disposed behind the vehicle seat, the vehicle seat assemblyseat comprising: a seat bottom and a seat back extending adjacent theseat bottom, the seat bottom comprising a structural support member madeof a structural foam material and a cellular foam seat member supportedon the structural support portion, the structural foam material beingmore resilient than the cellular foam seat member, the structuralsupport member being supportable on the vehicle floor, the structuralsupport portion, when supported on the floor, being configured toprovide an air flow passage extending under the seat bottom to provideair flow to the power source.
 2. The vehicle seat assembly of claim 1wherein the seat bottom has a front, a back, a top, and a bottom, thestructural support portion having a bottom surface forming at least asubstantial portion of the seat bottom and the foam seat cushion havingan upper surface forming at least a substantial portion of the top ofthe seat bottom, the structural support portion having at least twoopposed side walls extending between the front and the back of the seatbottom and being supportable on the vehicle floor, the vehicle floor andthe opposed side walls cooperating to form at least part of the air flowpassage.
 3. The vehicle seat assembly of claim 2 wherein the opposedside walls extend substantially at an angle between the front and theback of the seat bottom, and the seat bottom having a plurality ofstructural members extending from the seat bottom surface of the seatbottom and being supportable on the vehicle floor, the structuralmembers and the side walls providing support for the vehicle seatassembly.
 4. The vehicle seat assembly of claim 1 wherein the structuralsupport portion is made of a polymeric material having a density of atleast 1.75 pcf when measured in accordance with ASTM test method No.D3575 and a compressive strength, at 50% strain, of 0.30 to 0.50 MPawhen measured in accordance with ASTM test method No. D3575.
 5. Thevehicle seat assembly of claim 4 wherein the polymeric material has atear strength of 1.8 to 3.2 gms/mm when measured in accordance with ASTMtest method No. D3575.
 6. The vehicle seat assemble of claim 1 whereinthe power source comprises a battery.
 7. The vehicle seat assembly ofclaim 2 wherein the structural support portion has a front wall havingan inlet opening, the inlet opening comprising the entry to the airpassage.
 8. The vehicle seat assembly of claim 7 further comprising atrim register supported within the inlet opening.
 9. The vehicle seatassembly of claim 1 wherein the foam seat cushion is adhesively securedto the structural support portion.
 10. The vehicle seat assembly ofclaim 1 wherein the structural support portion has an average thicknessof 5 to 100 mm and a compression strength at 50% strain of 0.30 to 0.50MPa, as measured in accordance with ASTM test method No. D3575.
 11. Thevehicle seat assembly of claim 1 wherein the structural foam materialcomprises expanded polypropylene (EPP).
 12. A vehicle battery packcooling system, the system comprising: a vehicle floor; a seat assemblysupported on the vehicle floor; and a battery pack for providing atleast some of the power to the vehicle, the battery pack being supportedbehind the seat assembly; the vehicle seat assembly seat comprising aseat bottom and a seat back extending generally vertically from the seatbottom, the seat bottom comprising a structural support portion made ofa first polymeric material and a foam seat cushion supported on thestructural support portion, the structural support portion beingsupportable on the vehicle floor, the structural support portioncommunicating with the vehicle floor to form at least a portion of anair flow passage extending under the seat bottom, and the structuralsupport portion further having a plurality of spaced-apart memberscooperating with the vehicle floor to help support the seat assembly onthe vehicle floor.
 13. The vehicle battery pack cooling system of claim12 wherein the first polymeric material has a tear strength of 1.8 to3.2 gms/mm when measured in accordance with ASTM test method No. D3575.14. The vehicle battery pack cooling system of claim 12 wherein seatbottom has a front, a back, a top, and a bottom, the structural supportportion having a bottom surface forming at least a substantial portionof the bottom of the seat bottom and the foam seat cushion having anupper surface forming at least a substantial portion of the top of theseat bottom, the structural support portion having at least two opposedside walls extending between the front and the back of the seat bottomand being supportable on the vehicle floor, the vehicle floor and theopposed side walls cooperating to form at least part of the air flowpassage.
 15. The vehicle battery pack cooling system of claim 12 whereinthe foam seat cushion is adhesively secured to the structural supportportion.
 16. The vehicle battery pack cooling system of claim 12 whereinthe structural support portion has an average thickness of 5 to 100 mmand a compression strength at 50% strain of 0.30 to 0.50 MPa, asmeasured in accordance with ASTM test method No. D3575.
 17. The vehiclebattery pack cooling system of claim 12 wherein the first materialcomprises an expanded polyolefin (EPO).
 18. The vehicle battery packcooling system of claim 17 wherein the first material comprises expandedpolypropylene (EPP).
 19. A method of cooling a vehicle battery packlocated in a vehicle having a vehicle floor, the method comprising:supporting a seat assembly on the vehicle floor; supporting a batterypack for providing at least some of the power to the vehicle behind theseat assembly; the vehicle seat assembly comprising a seat bottom and aseat back, the seat bottom comprising a structural support portion madeof a first material and a foam seat cushion supported on the structuralsupport portion, the first material being at least as resilient as thefoam, the structural support portion communicating with the vehiclefloor to help form an air flow passage extending under the seat bottom;and directing air flow through the air passage under the seat to providecooling to the battery pack.
 20. The method claim 19 wherein the seatbottom has a front, a back, a top, and a bottom, the structural supportportion having a bottom surface forming at least a substantial portionof the bottom of the seat bottom and the foam seat cushion having anupper surface forming at least a substantial portion of the top of theseat bottom, the structural support portion having at least two opposedside walls extending substantially at an angle between the front and theback of the seat bottom and being supportable on the vehicle floor, thevehicle floor and the opposed side walls cooperating to form at leastpart of the air flow passage, and the structural support portion furtherhaving a plurality of spaced-apart support members cooperating with thevehicle floor to help support the seat assembly on the vehicle floor.